/*
 * Tencent is pleased to support the open source community by making spring-cloud-tencent available.
 *
 * Copyright (C) 2021 Tencent. All rights reserved.
 *
 * Licensed under the BSD 3-Clause License (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * https://opensource.org/licenses/BSD-3-Clause
 *
 * Unless required by applicable law or agreed to in writing, software distributed
 * under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
 * CONDITIONS OF ANY KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations under the License.
 */

package com.tencent.tsf.unit.core.algorithm;

import java.util.Map;

import com.tencent.polaris.api.utils.StringUtils;
import com.tencent.tsf.unit.core.TransformAlgorithmEnum;
import com.tencent.tsf.unit.core.exception.ErrorCode;
import com.tencent.tsf.unit.core.exception.TencentUnitException;

public class ModAlgorithm implements IUnitTransformAlgorithm {

	private final Map<String, Object> options;

	private final int mod;

	public ModAlgorithm(Map<String, Object> options) {
		this.options = options;
		mod = Integer.parseInt(String.valueOf(options.get("mod")));
	}

	@Override
	public String getName() {
		return TransformAlgorithmEnum.MOD.name();
	}

	@Override
	public String transform(String cid) {
		if (StringUtils.isEmpty(cid)) {
			return null;
		}
		try {
			long id = Long.parseLong(cid);
			return String.valueOf(id % mod);
		}
		catch (Exception e) {
			throw new TencentUnitException(ErrorCode.CUSTOMER_NUMBER_TRANSFORM_ERROR, "format invalid, customNumber:" + cid, e);
		}
	}
}
